The SME sector plays a very important role in the national economy, accounting for most enterprises, half of the workforce in the country and a third of sales revenue of the country. So, the current economic state of the country depends largely on the activity of SMEs. Given the diversity of their ownership forms, there is a need to determine the contribution of companies with different forms of ownership in the SME sector. The purpose of the study is to identify the contribution of these SMEs and its evolution, depending on the types of ownership forms of enterprises based on studying their activity indicators. Research methods that were used include: analysis of statistical data, comparison, chain indices, graphs. The results showed that private enterprises have primacy, virtually, at all activity indicators, followed by those with wholly or partly foreign capital and with wholly or partly public capital